Beginning during the mid-1980's wireless communication carriers began installing self-standing communication antenna support structures designed and authorized for their own specified usage. However, due to the auctioning of the available radio spectrum by the Federal Communication Commission in 1994, the demand for viable communication antenna support structures has exploded.
The proliferation of these unsightly support structures has incited much public opposition to any new support structure construction. Beginning in the mid-1990's communities began enacting stricter zone requirements designed to stop additional installations of these communication antenna support structures (e.g. monopoles). This, in turn, has forced the wireless industry in the United States to “co-locate” or share the same communication antenna support structures, that is, multiple carriers now lease or purchase positions on existing monopoles.
In order to fit the needs of multiple carriers, thousands of these monopoles must be modified or retrofit to support the additional antennas. A typical monopole is made of a hollow, steel pole anchored to a foundation and whose interior is constructed and arranged for safely routing the communication cables to and from the various antenna located approximate the top. The addition of new carriers to a monopole is but one reason for the creation of openings by qualified welders within the monopole support walls. These openings are designed to provide access into the monopole's interior.
As would be expected, these crude openings compromise the structural integrity of the monopole walls, thereby requiring additional structural support by way of metallic devices (also known as portholes or access ports) sized to completely penetrate the crude opening. Once situated within the crude opening of the monopole, the porthole must be welded in place by a qualified welder using the necessary welding techniques, as set forth in the structural welding code set forth in the American Welding Society (AWS) D1.1 General Requirements. If installed properly, the porthole will lend the necessary structural support to the opening.
To this point porthole installation has been mostly unregulated, leading to numerous problems including installation hazards which result in the diminished structural integrity of the monopole. For example, currently during the installation of commercially available portholes the worker must cut the crude opening into the monopole and place an appropriately sized porthole within the crude opening. Next, the worker permanently adheres the porthole to the opening by weld reinforcement. The worker must weld a filler metal into the joint (i.e., distance between the surface of the monopole and the porthole). Typically, the welding occurs along the outside surface of the monopole, resulting in what is referred to as “partial joint penetration” (PJP). In a partial joint penetration weld the weld metal does not extend the entire distance as measured from the weld face into the joint. This creates in a weldment that does not meet proper welding specifications as defined by the AWS.
The conscientious worker will then have enter inside the cramped interior of the monopole and perform another back weld between the porthole and the inner surface of the monopole. Again, this can result in an undesirable partial joint penetration weld.
All debris inside the monopole should be removed and disposed of prior to any welding. Failure to inspect the interior of a monopole for debris (e.g., vegetation, animals, paper, fuel, etc.) has resulted in fires within the monopole, which ultimately destroy the monopole structure and the equipment therein.
Currently, inspection of the monopole interior involves the use of a flash light and mirrors. The instant inventor has developed a camera system which may be inserted into the interior of the monopole to readily identify potential fire and safety hazards, for example, debris that might ignite from contact with molten meal or spatter created by the welding process.
Thus, what has been heretofore lacking in the art is a porthole apparatus having an internally connected backing plate and a method of installing the same.